


Narcotic Daylight

by weeping00willow



Category: Doctor Who (2005), Sherlock (TV)
Genre: Action/Adventure, Case Fic, Crossover, Gen, M/M, Pre-Slash, Work In Progress
Language: English
Status: In-Progress
Published: 2012-05-03
Updated: 2012-05-09
Packaged: 2017-11-04 18:48:33
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 8
Words: 15,233
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/397049
Author URL: https://archiveofourown.org/users/weeping00willow/pseuds/weeping00willow
Summary: <blockquote class="userstuff">
              <p>The first time Sherlock saw a man fall from the sky...</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> This is my first attempt at fanfiction in this fandom, so please bear with me. *grins* Comments are much appreciated, do tell me what you think.
> 
> Disclaimer: I do not own any of the characters mentioned in this story.  
> The title is from a poem called "Narcotic daylight" by Carla Vicknair.

The lights of the main deck were blinking furiously and the floor kept shaking, throwing him this way and that, as the Tardis spun through space and time. The blastwave from the supernova had indeed pushed the Tardis free from the black hole’s gravity pull, but in doing so had damaged the ship’s engine. There was no way of controlling its trajectory now, and the main power core was steadily becoming unstable. He had to either shut it down, or risk being blown to smithereens, but that would mean stranding himself inside the time vortex without any chance of escape.

The Doctor made a last minute choice. Since he couldn’t plot a new trajectory anymore, he pulled up the second to last destination he’d recorded on the Tardis navigation system and steered the ship towards that last point in time, hoping it would work. Four seconds until core overload. He caught a glimpse of the screen just before he pulled the emergency failsafe switch:

London, August 14th 1998 

That’ll have to do. 

Then came a rush of noise and pain, ending in darkness.

*

Sherlock had just finished injecting the opiate into his left arm. He let go of the tourniquet from between his teeth and stuck the needle and syringe back into their case. No need to leave evidence behind, thank you very much. He leaned back against one of the wooden pillars of the dock and closed his eyes. He could already feel the drug taking hold and muffling the constant bustle of his thoughts. This was the only reprieve he could snatch for himself. And it made his obnoxious older brother mad, therefore increasing its appeal. Closing his eyes, he pictured the drug’s molecular structure and traced the compound’s pathway through his veins, timing his neural response to the added stimulus. His thoughts began to scatter pleasantly. 

That’s when he heard the crash.

Opening his eyes, Sherlock scrambled to his feet, looking for the source of the noise. His eyes focused on a tuft of smoke rising from the Thames abouth half a kilometer downstream. He started running towards it. There was no one else around these parts at two o’clock in the morning. Visual data indicated either an explosion or a crash of some sort. His head was spinning and it was hard to coordinate his limbs, as he skidded to a halt near the area in question. There was no more smoke to be seen, nothing looked out of place. He turned round, scanning the ground for clues, but found nothing. Whatever it was, it must have fallen into the river. His brain felt muddled by the lingering effects of the drug and he could not concentrate. He took a few steps further towards the river bank and spotted a lump floating on the water’s surface. It was a body, face-down, flowing with the current. Sherlock took a moment to calculate the position, trajectory and odds of success of a hypothetical rescue, wondered why at all he cared, then, seeing as though nobody else but him was available, took the chance anyway and jumped into the stream. 

He waded through the cold water, trying to keep the body in sight, until he reached it. Turning it around, he saw that it was an unconscious man. Chances were he’d be already dead, but he didn’t have the means to check for sure, so he started swimming towards the bank, towing the man with one arm. Reaching the shore, he dragged the man onto the ground and took a second to catch his breath. Details spun into his mind with the usual speed: young, late twenties, dark hair cut in short spikes – indication of rebellious tendencies, but not overt enough to no blend into a crowd; cut bleeding above his right eyebrow – concussion perhaps, due to position and depth; trenchcoat, tweed suit and tie – casualness of attire indicating choice rather than job requirement; slender build yet hinting good muscle definition, hands smooth with barely noticeable calluses and fingernail shape - signs of mainly intellectual activity interspersed with physical exercise; sneakers on his feet with soles weel worn suggesting an active lifestyle that included running; portions of his clothes singed by fire confirming his previous assumption of an explosion or some type of accident. 

Sherlock checked the man for vitals. He could find none. His mind spun into something akin to panic; he had never attempted to save another life before. Sure, he had seen people both alive and dead (what with his experiments at the University morgue), but never in that in-between state where their lives hung by a thread, a thread which he now held in his own hands. 

Conjuring up his theoretical knowledge of first-aid, he tipped the man’s head back to ensure access to his airways, clipped his nose between two fingers and opened his mouth with his other hand. He lowered his mouth to his and blew, forcing the air into his lungs. Then he started the rhythmical compressions to his chest, counting to five. Repeat. The man showed no sign of recovery.

“Come on!” he muttered under his breath and repeated the process again. 

His arms began to shake. He kept pressing. Just when he’d started to think it was all in vain, the man suddenly flinched upwards and started coughing out water. Sherlock breathed a sigh of relief. He couldn’t understand why saving this man was so important to him, he’d never cared much for other people before.

Then, the man locked his eyes to him and Sherlock’s breath caught. He could see a lifetime of battles won and lost inside those eyes, a world of pain and loss shadowed by lingering hope, a mind so full of knowledge yet craving more, a life so full and marked with experience that no other man his age should possess. Sherlock could almost read infinity in those eyes. The more he looked, the more he felt his lungs constrict with an odd sensation, not unlike the effects of the drug he had previously taken. Then, the stranger pushed himself up on his elbows and smiled at him.

“Well, hello there,” he said in a voice that was part surprise, part amusement.

That’s when Sherlock registered that his own hand was still lingering on the man’s chest, and a second wave of shock came when he realised what he could feel under his palm: four synchronous heartbeats, two on the left, two on the right; two hearts! 

“How is that possible?” he whispered in awe. He knew all the inner workings of the human body, all the parts and processes, this could not be.

He held the man’s stare, pressing his hand to his chest, unable to blink or move as if in fear the mysterious stranger would disappear if he took his eyes off him. That’s when he heard the sirens and the rumble of a helicopter approaching from above. This seemed to spur the man into action.

“Quick, help me up!” he said, and grabbed Sherlock’s arm pulling himself unsteadily to his feet.

While Sherlock could do nothing but watch, still in shock, the man pulled something from his coat pocket, a long, thin metal device which he pointed towards the river and started moving it around. It made a whirring sound which seemed to increase when he turned it in a particular direction, towards the place where Sherlock had first seen him floating in the water.

“Ah!” he exclaimed. “There you are.”

He started babbling excitedly:

“I can’t believe it actually worked! It was a one in a million chance and even then the impact could have destroyed the outer shield and caused the equivalent of a stellar implosion!”

Sherlock shook himself out of his stupor and cleared his throat pointedly. The man spun around to face him, with a large excited smile on his face and said:

“Oh, yes, of course, how rude of me! Thank you for saving my life… I didn’t catch your name…”

“Sherlock Holmes”, he managed to say.

The stranger stepped forward and caught Sherlock’s hand in a tight grip, shaking it. It sent a warm, tingling sensation through his arm, making him blink in confusion.

“Nice to meet you, Sherlock! I’m the Doctor,” he said.

Before Sherlock could enquire further, the man spun towards the sound of the sirens that seemed even closer, and said:

“Sadly, I must leave now. If my guess is correct, those are government helicopters heading our way, they must have picked up the crash on their atmospheric sensors and it wouldn’t do to stick around for them to catch up.”

He turned towards the river and started walking with renewed vigour. Sherlock took a couple of steps to follow him, bewildered.

“Where are you going?” he asked. 

“To get my Tardis back, of course!” the man who called himself the Doctor said as he reached the river bank.

He turned towards Sherlock and smiled.

“Perhaps we’ll meet again, Sherlock,” he said with a wink, then threw himself into the river.

“Wait!” he shouted and made to move.

The helicopters had reached their destination and were now hovering above Sherlock’s head, casting beams of blinding white light on the ground until they settled on his own form. “Stay where you are!” a voice blasted through a speaker, as the police cars approached.

Sherlock ignored them and could only stare as a blue, muted light began to pulsate beneath the surface of the water, and a sound like scraping metal could be heard in time with the blinking blue light, under the roar of the helicopters. Then the light and the strange sound stopped, just as a sleek black car approached from behind.

The door swung open and out came the suited figure of his brother, Mycroft. Youngest Secret Service commander in British history, as he often liked to point out.

“Oh, brother mine,” he exclaimed in that annoying long-suffering tone of his. “Why am I not surprised to find you here?” A sigh. “Come along, now.”

Sherlock shot him one of his deadliest glares, but Mycroft remained unfazed. He glanced one last time back to the river, somehow knowing that the stranger who called himself the Doctor was now gone, then turned around and followed his brother. His palm still tingled where it had touched the other man’s hand.

 


	2. Chapter 2

**Summary for the Chapter:**

> Thirteen years later...

August 14th 2011

 

“There’s a woman claiming that her husband ‘s been missing for three days…” John read from the laptop screen.

“Boring,” Sherlock interrupted from where he lay on the couch, eyes closed. “He’s cheating on her.”

John sighed and opened the next e-mail.

“A man here says that he’s been receiving threatening phone calls for the past week…”

“Boring. Next!”

“Huh… A woman says she hears strange noises coming from her pantry every night and is asking you to investigate.”

“For crying out loud!” Sherlock exclaimed. “Do these people think I’m from the bloody pest control, or what? Next!” he huffed and rolled over with his back to John.

“Well,” John continued reading, clearly amused. “There’s another little girl asking you to come find her missing cat…”

“You’re enjoying this, aren’t you?” Sherlock accused, narrowing his eyes at John over his shoulder.

When John couldn’t hide a snigger, Sherlock jumped down from the couch and started pacing the room.

“I’m bored, John!” he snarled petulantly. “I need a case, find me one!”

“The little girl does offer to pay…” John goaded, with a smirk.

“I’d rather comb my brain with a pitchfork, thank you very much!” Sherlock snarled, picking up the Tchokwe spear he’d kept from last week’s case and stabbing the air in front of him with it.

“Careful where you point that thing!” John warned, ducking his head behind the screen. “Christ, you’re like an addict craving his next fix!”

“I feel like I’m going mad!” Sherlock took aim with the spear and pitched it towards the wall, stabbing the yellow smiley face painted there right in the middle. “I need something to make me think, I can’t stand this dullness anymore. I can’t walk around all day with my mind dimmed to the brainwave of a turnip like you and everyone else!”

“Well, you can start by explaining the state of that wall to Mrs Hudson if you still want to keep that thick head of yours attached,” John huffed in annoyance and stood up. “I’m going to take a walk.”

“Oh, come on, John,” Sherlock wheedled. “Stop being so testy, you know it’s not your fault that you fell into the less intellectually potent 99 % of the gene pool…”

“…Aaand I’m leaving now,” John said, grabbing his coat.

“John! Come on, don’t leave me here to get bored by myself!...”

That’s when the phone started ringing on the coffee table.

“Well, aren’t you going to get that, John?” Sherlock asked. “Maybe it’s a new case.”

“It’s your phone!” John couldn’t hide his outrage anymore.

“But it’s lying over there and I’m standing here,” Sherlock pointed out as if to a particularly stubborn three year old. “Go on, please?”

John threw his deadliest glare in his direction and stomped to the table, grabbing the mobile phone.

“Hello!” he growled into the speaker, scowling at Sherlock’s satisfied grin. “Detective Inspector Lestrade, nice to hear from you!” “Yes, he’s standing right here.” “Yes, he’s gotten to the throwing-sharp-objects-across-the-room stage…” “Of course, here you go.”

He pushed the phone into Sherlock’s eager hand and bit out: “It’s for you!”

“Lestrade, tell me you’ve got something for me!” he said. He listened to the brief exposition on the other end of the line, occasionally grunting his assent, then cut off the call with a final “We’ll be right there!”

Quickly putting on his shoes and grabbing his coat, he grinned: “Hurry up, Watson, we’ve got a new case!”

John rolled his eyes and followed him out the door.

 

*

 

43A Rydon Street was the nondescript flat of an equally nondescript middle class family man who had disappeared over night.

“Precisely what timeline are we talking about?” Sherlock dove full on into the investigative mindset.

“At about three o’clock in the morning, Russel Cox woke up to get a nightcap as per usual, from what his wife told us,” Lestrade informed. “He went into the kitchen, turned on the tap on the sink, then a minute later his wife heard the sound of breaking glass and a shout. When she rushed to see what was happening, Cox had vanished from the room.”

“What do you mean, ‘vanished’?” John asked.

“I mean he literally disappeared without a trace,” Lestrade couldn’t hide his confusion. “All doors and windows were found locked from the inside and the wife claims she found no one else in the apartment aside from herself and her six year old son.”

“So why did you call me here for what appears to be a missing persons case?” Sherlock asked. 

“Well, that’s the thing,” Lestrade said. “Russel Cox is the third person this week to vanish in similar circumstances. First one was Penny Clayworth, 53, financial consultant and single mother of two, found missing from her bedroom in the morning by her eldest daughter Clarice, no sign of forced entry and all doors and windows bolted shut. That was four days ago. The second one, Clark Turner, 24, medical student, sharing a flat with two friends, vanished two nights ago in a similar fashion. No one has heard from them since, there were no personal items missing, no money, clothes or identity papers, nothing inside their homes was disturbed. They were simply there one moment and gone the next!”

“I’m going to need the files of all three missing persons and as detailed an account as possible as to their every step taken these past two weeks.” Sherlock mused, as he paced the kitchen carefully, scanning the floor and furniture.

“Hmm, what is that puddle over there on the floor?” he asked, pointing towards a spot in front of the sink.

“Well, I suppose it’s water, seeing as though he’d been looking for a drink and dropped the glass to the floor when… something happened to him,” Lestrade said.

“Wrong,” Sherlock muttered, while squinting to catch a better sight of the floor in the sunlight. “The shape of the puddle is obviously inconsistent with the spatter a broken glass of water would have made, and the glass shards show no signs of having held anything liquid for the past 24 hours. Also, the volume of liquid on the floor is clearly larger than a mere glassful.”

“Oh, come on, Sherlock,” Lestrade huffed. “The man was standing next to a running tap, if someone grabbed him he would have flung some water around, for God’s sake!”

“Improbable,” Sherlock cut him off. “Block the windows and door and bring me an ultraviolet lamp!” he told the group of forensic specialists scattered around the room.

“Wait just a damn minute there,” Anderson piped up. “Who do you think you are barging in here and giving us orders?”

“Anderson, please!” Lestrade shot him a look.

The man huffed and stomped out of the room, while John and two other policemen began to close the drapes on the windows to block the light. Anderson came back with the UV lamp and handed it over, muttering under his breath about arrogant amateurs who think they own the place.

Sherlock crouched down to the floor and turned on the lamp, casting the bluish light over the spot.

“Well, John, what do you think?” he asked.

“Definitely organic,” John answered as he traced the contours of the dried puddle. “Would need to run some tests to be sure, though.”

“Precisely,” Sherlock agreed. “I’m going to take a sample of this as well, if you don’t mind.” He said, swiping a cotton swab through the dried liquid and dropping it into a sterile bag.

Anderson’s irritated “Hey, no tampering with the evidence!” went unacknowledged.

“Hmm, interesting…” he murmured and moved the light further along the tiles. A handful of thin, barely there, squiggly lines stretched away from the puddle across the floor, disappearing under one of the cupboards.

“Help me move this,” Sherlock said, and with John and Lestrade’s help, he pushed the cupboard aside, revealing the kitchen’s sewer cap. The tracks stopped there.

“What on earth is that?” gasped Anderson.

“Detective Inspector Lestrade,”Sherlock said. “I think you’ve got a much more complicated problem than we thought.”

 

*

 

“I still can’t believe Craig got your number!” Amy said as they approached the house on 79A Aickman Road. 

“Well, we did the whole memory swap thing, it figures that he would have remembered something like that,” the Doctor said. “Besides, we gotta have someone else besides Winston Churchill calling that line.”

“Nice looking house,” Rory said, as they climbed up the front steps.

“Definitely looks better without a giant spaceship nested on top,” Amy replied.

The door suddenly swung open and Craig ushered them in with an excited “I’m so glad you’re here!”.

“Doctor!” Sophie rose from the couch to meet them.

“Well, hello there, Sophie!” the Doctor exclaimed and ran to give her a hug, giving her a peck on each cheek in that funny way he thought people greeted nowadays. “There’s something different about you…” he squinted at her face, while Rory and Amy properly introduced themselves to Craig.

“Shh!” Sophie whispered, casting a glance towards her new husband with a smile. “I haven’t told Craig yet, but we’ve got a little one on the way!”

“Oh, that’s brilliant!” the Doctor beamed, hugging her again. “Congratulations!”

They settled on the couch and chairs around the living room table, and, while Sophie poured the tea, they asked for details about the so-called emergency Craig had mentioned.

“I thought we were out in the clear after you dealt with that spaceship half a year ago,” he began. “I mean, what are the odds of something like that happening again in this house? 

But immediately after it happened, I knew we needed your help.”

“Yes, I get that, Craig, but what exactly happened?” the Doctor asked.

“Well, you see, after you left, we put up an ad for a new lodger,” Craig explained. “We needed the rent, what with Sophie taking classes at the local veterinary school and all, and we’d just got married, so… Anyway, Clark was a great guy, a medical student, seemed kind of fitting, to trade in one doctor for another. Although no one else can ever replace The Doctor…”

“Sweetie, you’re babbling again,” Sophie admonished affectionately over her cup of tea.

“Right, right,” Craig said. “The thing is, everything seemed well enough until a couple of days ago, out of the blue, Clark vanished into thin air!”

“Vanished?” the Doctor perked up. “How exactly did he manage that?”

“I have no idea!” Craig said. “He went to bed as usual, and when Soph went to give him his wake up call like every other morning, to get a ride together to the Uni, he was gone. All of his things were left behind, and all the doors and windows were locked, from the inside. Of course, we called the police, but they didn’t find anything either. That’s when we decided to call you. I’ve seen enough people disappearing out of the blue to know when something’s not right.”

“Interesting,” the Doctor mused, rubbing his chin. “Can I see the room?”

“Of course!” Craig leapt up from his seat, striding towards the door. “We kept everything as it was. Well, after the police left, at least.”

They entered the room and the Doctor pulled out his sonic screwdriver, turning around to scan the room with it, then looked at the readings.

“Yes, there’s definitely been alien activity in this room at some point,” he confirmed.

“I knew it!” Craig exclaimed. “Do you think it has something to do with that ship again? Do you think it’s back?”

“I’m sure it’s just a coincidence,” said Sophie, worrying her lower lip with her teeth. “Right, Doctor?”

“Oh, that ship is definitely not coming back,” he said. “But it could be something related to it, maybe…” he continued to search the room, pulling drawers open and rifling through the wardrobe. “Maybe some other creature drawn here by the lingering effects of the time discontinuity triggered by the ship, maybe something else entirely… Oh! Hello!” he said, pulling back the bed sheets to reveal the mattress.

It looked as though it had been soaked through at some point and had a slightly mouldy scent.

“What is it?” Amy asked.

“Looks like some kind of residue,” the Doctor answered as he leaned forward to sniff at it.

“Oh, that is disgusting,” Rory scrunched up his face.

“Just need to get a few things,” the Doctor bounced to his feet and ran out of the room.

Sounds of opening and closing doors and rummaging could be heard for a minute, before the Doctor came back carrying a pair of scissors, the glass container from the coffee maker, a bottle of mouthwash, a pack of Earl Grey tea and a Duracell alkaline battery snatched out of God knows where. He dutifully poured all the ingredients into the transparent pot, then cut out a strip of the soaked material of the mattress and let it drop into the pot. He then covered it with a lid and started shaking it for a couple seconds, dropped the alkaline battery inside and powered the sonic screwdriver beneath it. The concoction inside quickly changed its colour from a vague murkish green to bright crimson, interspersed with light green patches.

“Hmm, just as I thought,” the Doctor said, frowning at the pot. “Human DNA combined with something alien. Can’t determine what, though, I need to take a sample back to the Tardis to check the database.”

“So, what does this mean?” asked Sophie. “Is it going to help us find Clark?”

“If there is anything left of him to find at this point, maybe…” the Doctor said distractedly while he cut another strip of cloth from the bed and dashed out of the room to get to the Tardis.

Amy shrugged with an apologetic look to the bemused couple standing near the door: “Don’t worry, he knows what he’s doing… most of the time.”

 

*


	3. Chapter 3

Sherlock and John’s cab pulled up in front of 79A Aickman Road just as Lestrade and two police cars were approaching from the other side.

“Let me guess,” John said. “You’ve finished analysing the compound.”

“I was checking the first victim’s address again, at 15th Draycot Close when the test results came back,” Lestrade supplied, as they hurriedly approached the house. “We’ve never seen anything like it! But it definitely contains traces of the vic’s DNA. We’ve called in a biohazard team to secure the areas, we fear it may be a new form of virus or biological weapon…”

“Why on earth did you do that?” Sherlock snapped. “All right, all right,” he calmed himself down. “Thanks to you bloody idiots, we’re on a time limit, again! Let’s hurry up and get this over with, before…”

The door opened and the befuddled face of Craig Owens greeted them.

“Detective, I didn’t expect to see…” he began.

Sherlock pushed himself inside without even bothering to speak, followed by John, and headed towards the room in question.

“Mister Owens,” Lestrade was flashing a warrant in front of Craig’s face. “We need to secure the premises at once. You and your wife need to vacate the house immediately.”

“Excuse me!” Sophie appeared in the hallway just as Lestrade and the policemen were entering. “This is our home! You can’t just throw us out! Besides, you didn’t find the need to do this two days ago, why…”

The Detective’s reply was cut off by Sherlock’s outraged yell from inside the room:

“Who did this?!”

As the others approached the threshold, they could see the rumpled chaos of the room – drawers hanging half-open, bed sheets torn asunder, clothing flung this way and that. Sherlock squinted at the ripped open mattress.

“Did you do this?” he eyed Craig critically. “Of course you didn’t do this,” he muttered to himself, bending over to check under the bed.

“Why did you tamper with police evidence, mister Owens?” Lestrade asked.

“Now wait just a minute here,” Craig snapped. “This is my bloody house and I’m allowed to do whatever I bloody please in it! I specifically asked you two days ago and you said it was no longer a crime scene, so it’s none of your business what I did since then.”

Sherlock was crouched on the floor, tracing something only he could see across the carpet towards the eastern corner of the room. He stopped in front of a dresser and pulled it from the wall, revealing an old fashioned wrought iron air vent.

“Lestrade, I need the plans of this building as soon as possible,” he said, jumping to his feet and exiting the room. “And get me the London sewage system plans too, while you’re at it,” he added, stopping in the middle of the living room to look around.

“Hmm, interesting,” he murmured, as he bent over the couch with his pocket magnifying glass.

“Who is this guy?” asked Sophie confoundedly, as she watched.

Whatever reply John had opened his mouth to give was cut off as the front door opened and a handful of men wearing hazmat suits entered the house, followed by two men dressed in sharp black suits, one of them holding an umbrella in his right hand.

“Mycroft,” Sherlock bit out through his teeth. “Took you long enough.”

“I’m sorry, gentlemen,” Mycroft said, looking in Lestrade’s direction. “But I’m going to ask you all to leave the premises immediately. This is officially a matter of national security.”

Turning towards the other suited man, he added: “Agent Preston, begin containment procedure immediately.”

As the men in hazmat suits began ushering the other policemen and a disgruntled Owens couple out of the house, Mycroft turned to Sherlock.

“That means you too, little brother.”

“What’s going on here, Mycroft?” Sherlock asked. 

“I’m afraid I cannot tell you that,” he said. “And I also know that you will want to pursue this further, but I am asking you, Sherlock, just this once, do what is best for you and let the professionals do their jobs. This is a lot bigger than a few missing people and you are not equipped to handle it.”

“Whatever it is, Mycroft, you need my help.” Sherlock insisted.

“Not this time, little brother,” the man said. “Now, if you don’t mind…” he pointed towards the door with a dismissing gesture.

“We’ll see about that,” Sherlock huffed and with a last withering glare aimed at his brother, he left the house.

“What’s going on, Sherlock?” John intercepted him as he made his way back to the main street, bypassing rows of government cars and containment teams unloading various equipment from their vans.

“Mycroft’s department must have gotten wind of the samples Lestrade sent to the lab to analyse,” Sherlock said. “It was only a matter of time until he took over the investigation. He seems to think he can keep things from me. He should know better.”

“But what about the room we just saw?” John asked as they rounded the street corner, trying to keep up with Sherlock’s hurried pace. “It looked like someone took the place apart trying to find something.”

“Indeed,” Sherlock confirmed. “The Owens definitely know who, and they’re protecting them. They can’t have gotten far.”

“How do you know that?” John asked.

“There were five recently used cups of tea in the sink,” Sherlock explained as he raised an arm to hail a cab. “Two of them still wet, left out to dry, three still with traces of tea on them, indicating that the wife was in the process of doing the dishes when we arrived. That means we must have missed them by about fifteen minutes at most. We have the Owens couple, which leaves three other people unaccounted for. Judging from the traces I found on the couch, we are looking for two male and one female.”

“Now how could you possibly know that?” John asked just as a taxi pulled over in front of them.

After they got in the car, Sherlock elaborated: “ Strand of hair, natural red, fifteen inches long, judging by length and pigmentation belonging to a woman in her mid-twenties, found on the backrest of the couch, in the middle. From the dents left in the cushion, she was sitting between the two men, closer to the one on her left, distance indicating physical closeness, perhaps a boyfriend; the one on the right marginally further away but not far enough, long-time friend or perhaps a past romantic interest seeing as though the woman was seated deliberately between the two almost as if unconsciously trying to deflect a conflict. The man on the right, he must have been the one asking questions, appears to be restless by nature seeing as though the seating imprint suggests a fair amount of fidgeting; two biscuits missing from the right side of the tray laid on the table indicates that he also has a sweet tooth, so we are looking at a fairly young metabolism, correlated with apparent height and weight to suggest a man between 20 and 30. Skid marks on the kitchen tiles and some of the drawers left open like in the bedroom we just saw are signs of someone looking for something specific, also in a hurry, most likely the man I’ve just described, someone who clearly knows more about what happened in that house and believes it is a matter of great urgency. The pattern of his search appears at first to be random, but closer observation hints at a well-defined goal and attempt to reach it by making use of items at hand, therefore improvisation and quick thinking. Seeing as though this man was granted access to all parts of the house by the Owens couple suggests a high level of trust, perhaps prior experience with a related incident, and they are obviously lying to protect him, which means they must have called him here on purpose, this was not a mere social visit. The tea kettle on the stove was still marginally warm, which means they can’t have stayed for more than ten to fifteen minutes, in which time this man apparently deduced the situation from the scant clues present at the scene and also found a lead to pursue, leaving in a hurry afterwards.”

Sherlock leaned back into his seat, half closing his eyes as a giddy sort of anticipation took him over at the thought of encountering a kindred spirit.

“Wow,” John exclaimed, clearly in awe. “And you got all that from a strand of hair. Amazing!”

“Why, thank you John,” Sherlock nodded, pleased, like every time his ego was stroked.

“What about the other two?” John asked.

“Who?” Sherlock asked distractedly, as his mind spun with the new information, trying to compile it.

“The other man and his redhead girlfriend,” John clarified.

“Irrelevant,” he dismissed. “This man is the only one that counts. We need to find him.”

“It seems to me that you are more interested in finding this guy than solving the actual case,” John looked at him dubiously, with the hint of a smirk. 

“Oh, come on, John!” Sherlock exclaimed, throwing him a look of pure outrage. “Get your mind out of the gutter.”

“I’m serious,” John insisted, with a smirk that clearly indicated the opposite of seriousness. “We’re talking about a man who appears to be ingenious, competent, unpredictable and has a knack for dangerous, possibly deadly situations. And you’ve deduced him from a biscuit and a cup of tea! I may not be the world’s only consulting detective, but I know how you tend to become obsessed…”

“You are obviously delusional,” Sherlock dismissed him with a wave. “We’re here,” he said, as the taxi stopped in front of a tall brick building in Clerkenwell.

“The Metropolitan Archives?” John asked, a little confused.

“Well, it’s unlikely we’ll get any help from Lestrade at this point, so I need you to get me the building plans for all three addresses of the victims and the London sewage system as well.”

“What are you going to do?” John regarded him suspiciously as he got out of the car.

“I’m going to pay a little visit to the CCTV headquarters,” Sherlock smirked. “See if the cameras have picked up any footage of our mystery man.”

“Sherlock!” John admonished.

“Yes, yes, John, carry on now,” he said and pulled the car door closed.

John shook his head at the departing vehicle and turned towards the building.

 

*


	4. Chapter 4

“Serashene, indigenous to the planet Lorikkee, third quarter of the Gliceadean System!” the Doctor exclaimed as he paced the main deck of the Tardis. “But what is it doing way over here?”

“Sera- what, now?” Rory asked.

“Serashene,” the Doctor explained, still pacing. “A race of serpent-like creatures that used to live in underground caverns on their home planet. Their tissues were said to be extremely sensitive to solar radiation, even though their bodies needed the heat to survive. A most unfortunate problem they chose to solve by splicing their DNA with that of other species, in an attempt to overcome their weakness. After centuries of experiments they finally devised a stable combination and the entire population went through a process that permanently modified their genes. But it had an unfortunate side effect on their reproductive process; within five generations, their offspring were no longer viable and the entire race eventually died out. At least this is what the accounts say… There has been no record of a living Serashene in over 60 million years. So how did one get here, on Earth?”

“And what is it doing to all these people?” Amy asked, looking at a screen on the Tardis’s console.

“People?” the Doctor stopped his pacing to approach the screen.

“I did a background check for similar events in the past year, like you asked,” Amy said. “And get this: two other people disappeared from their homes this week alone, leaving behind nothing but the same residue we found at Craig’s place. Or so the last police report says, it seems that the investigation was abruptly closed this afternoon, I couldn’t find anything else in their system.”

“Well, that’s probably the good old government, trying to keep things quiet,” the Doctor said. “If they get involved in this, there is no telling what kind of mess they’ll make. We have to find the creatures before they do.”

“What do you mean, ‘creatures’?” Rory asked. “You never said it was more than one.”

“Of course there is more than one,” the Doctor said. “They are obviously attempting to multiply. Probably found a way to use human DNA as a stabiliser. But why here? Why now?”

“How are we going to find them?”

“Well, you did say underground caverns,” Amy replied with a smirk, while she typed something into the search engine. “What better place to look than the London underground and sewage system?” she asked as she pulled up the plans on the screen.

“But that place is huge!” Rory protested. “How on earth are we going to search it all?”

“We need to narrow it down,” the Doctor mused. “When did you say the first person disappeared?”

 

*

 

“What have you got?” Sherlock asked just as John entered the flat on 221B Baker Street.

“Well, I did manage to get to the archive before closing time and got the maps you asked for,” John said as he pulled a stack of papers from their holder, splaying them on the living room table. “These are the plans for the three buildings in question.”

“Hmm, just as I thought,” Sherlock mused as he scanned the pages. “The ventilation system in Owens’ house has a point in which it intersects with the main sewer line.”

“Yes, but what does all this have to do with our three missing people?” John asked.

“Think, John,” Sherlock goaded. “What do three random people, of completely different backgrounds, social status and personalities, living in different parts of London, have in common? What is the one element that brings these people together every single day, without them even knowing most of the time?”

“The London Tube!” John exclaimed after a pause.

“Precisely,” Sherlock agreed. “From what I’ve gathered from Lestrade’s files, Penny Clayworth was a financial consultant working for the Camden branch of the ‘Hamilton-Webb’ firm, Clark Turner was a medical student who attended classes at University College and Russel Cox owned a small coffee shop near the campus. What brought them together five times a week was this,” Sherlock said as he pointed his finger to the map of London’s underground. “Euston Square Station. And fifteen feet to the east, parallel to the Tube…”

“The old sewer tunnel the city started working on last week, trying to convert it to a new Underground line!” Watson remembered. “The timing fits as well! Whatever happened to these three people, it began there.”

“We need to get down into those tunnels, John,” Sherlock said. “I’ll call for a cab while you get ready.”

“You mean we’re going into the sewers? Tonight?” John asked in a bland voice.

“There is no time to lose, John,” Sherlock said. “The disappearances occur on a two day schedule, we need to solve this case before tomorrow night, and we have a large area to cover between the two of us. I suggest we get right on it.”

“Okay, might as well find my waterproof boots, then,” John said with a tinge of disgruntled irony. “By the way, how did your search for that mystery man go?”

“All the security footage from the cameras on Aickman Road today are gone,” Sherlock said. “And not just Aickman Road, the surrounding area as well. Someone went to great lengths to cover up the visit the Owens received today.”

“Mycroft?” John asked.

“Who else?” Sherlock said. “That means Mycroft already knows who the man is and what he is looking for. And he is letting him. This case is getting more interesting by the minute.”

 

*

 

“Are you sure about this, Doctor?” Amy asked, as she waded through the ankle-deep murky water of the sewer, pointing her flashlight forward.

“The timing fits, Pond,” the Doctor replied, stepping over a particularly disgusting lump that may or may not have been a dead cat. He decided not to dwell on it.

“Somehow, traces of Serashene DNA were brought to Earth 60 million years ago, most likely when the asteroid that wiped out the dinosaur population hit. The samples must have lain dormant under the surface of the earth for millions of years, up until construction started on this particular spot one week ago.”

“So, they acted like some kind of virus, infecting people?” Rory asked.

“Makes sense if you think about it,” the Doctor said. “A dying race of brilliant creatures, a civilisation of biological engineers in their last days before total annihilation - they would do anything to preserve their legacy. So they build their own version of escape pods: fragments of their own DNA preserved in stasis, sent across the universe to wander until they find suitable conditions for them to develop, the perfect temperature, the perfect atmospheric makeup and, of course, the perfect living organism to which they can attach. The cells must have been designed specifically for it. A symbiote, meant for trial and error until it got it right.”

“But they didn’t get it right, not this time,” said Amy.

“No, they didn’t,” the Doctor agreed. “The human hosts must be incompatible with Serashene DNA. That goo we found on Clark’s bed, that was Clark! His body became unstable to the molecular level and just disintegrated to its most basic components, water and carbon.”

“So, do you think we’ll find more of them here?” Rory enquired.

“If some of them managed to survive the symbiosis, maybe, but we still need to find the source of the infection and stop it, before other people get killed.” the Doctor said, as they approached a point where the tunnel branched out in two different directions. “I think we should split up.”

 

*

 

“Why did we have to split up again?” John asked through the mouthpiece of his hands-free system. The signal was getting steadily worse the further he descended into the tunnel.

“Because we’ll cover more ground this way,” Sherlock’s voice sounded muffled and scratchy through the headphones. “Now keep looking and stop pestering me every five minutes.”

“Well, excuse me for checking to see that you’re still alive,” John muttered.

He was just about to round a corner when he heard footsteps coming from the opposite direction. He quickly turned off his flashlight and pulled out the handgun from his belt. “I think somebody’s here,” he whispered in the mouthpiece. When no answer came, he insisted: “Sherlock!”. But there only came the sound of static as a reply.

“Damn it!” he said under his breath and ducked as close to the wall as he could so he could ambush the intruder.

As the steps reached the bend in the tunnel, John mentally counted to three, then spun towards his target, with his gun poised and flashlight on, demanding: “Stop right there!”

“Whoa!” a startled yelp and a pair of raised hands met him.

John took a second to run the flashlight over the intruder’s form. A tuft of black hair flopping in the stranger’s eyes, high cheekbones, tweed jacket, pants a tad too short held up by a pair of suspenders and…

“Is that a bow tie?!” John asked in clear astonishment.

The man held up his chin and uttered in offended challenge:

“Bow ties are cool !” 

After a pause: “Could you not point that light in my face, thank you?”

John cleared his throat and relaxed marginally, but kept his gun firm. “And who are you supposed to be?”

“I’m the Doctor!” the man answered with a grin.

“What kind of doctor?”

“Just the Doctor,” the man shrugged, seemingly unconcerned by the gun trained on him. “Might I ask who you are?”

“What are you doing here?” John ignored his question.

“I could ask you the same thing, now, couldn’t I?” the so-called Doctor replied.

They stood there a couple of seconds staring each other down, until John decided that the man posed no threat and finally lowered his gun.

“My name is John Watson,” he relented. “My colleague and I are investigating a string of disappearances connected to this place. This could get dangerous, so you best be on your way.”

“Well then, John,” the man seemed particularly amused. “It seems that we are looking for the same thing. Might as well tag along, safety in numbers and all that.”

Try as he might, John couldn’t seem to find a reply to the ridiculousness of the whole situation.

“And where is this colleague of yours?” the Doctor enquired as he turned his head to scan the surrounding area.

“We split up and lost communications a while ago,” John answered. “Wait, what exactly are you doing here, again?”

“Oh, just trying to save Earth from planetary destruction again, all in a day’s work,” he muttered and craned his neck to look over John’s shoulder, while he pulled a map out of his pocket to squint at it. “There is a maintenance tunnel to the left, some… twenty feet the way you came, am I right? You must have passed it?”

“Yes, but the entrance was bolted shut,” John replied, still in a daze. “Seriously, what…?”

“No time for questions, John,” the Doctor replied, and started pacing in the direction John had come from. “We need to hurry.”

“Wait a second!” John sputtered, sprinting after the man.

They reached the rusted metal door which sealed off the maintenance tunnel, and the Doctor bent over to check the lock.

“Bolted from the inside,” he said. “That’s perfectly normal,” he added with a hint of irony, then pulled a strange looking gizmo out of his pocket and pointed it at the lock.

“What is that?” John asked.

“My sonic screwdriver, of course,” the Doctor stated, as if it were obvious.

The thing made a whirring sound and a second later, the lock clanked and the door cracked open an inch. The Doctor pushed the rusty door open all the way, with a loud squeal of its hinges and then carefully stepped inside, shining his flashlight to reveal a narrower tunnel that burrowed further into the earth.

“Is that some sort of secret government technology?” John asked, his mind spinning. He might have thought he’d stumbled into a strange parallel universe if he believed in such things.

“No,” the man said, refusing to elaborate, and they made their way inside the tunnel. “Be very careful where you step,” he added and took the lead.

A sudden thought made John pause:

“You’re him, aren’t you?” he said with sudden realisation. “The mystery man who visited Craig Owens today!”

“’Mystery man’, hmm, I kind of like the sound of that,” the Doctor smiled as he kept going.

“I should have known,” John grumbled. “What with the cheekbones and the - bow tie!”

“Hey!” the Doctor protested, but John just went on:

“You work with a redhead woman and another man, you’re fidgety, flighty, have a sweet tooth and like to improvise with kitchen appliances! I’m right, aren’t I?”

The Doctor suddenly stopped and turned, getting into John’s face and staring at him with suspicion.

“How did you know that?” he asked. “Have you been spying on me?”

“I’ve never laid eyes on you before,” John said. “But my colleague deduced all that from taking one look at the Owens’ living room this afternoon.”

“Remarkable!” the Doctor exclaimed with a surprised smile. “Who exactly is this associate of yours, again?”

“His name is Sherlock Holmes,” John said with a hint of pride, straightening his shoulders. “Most brilliant man I have ever met.”

The Doctor frowned and took a step back, rubbing his chin in thought.

“Sherlock Holmes… Sherlock... Where have I heard that name before?”

“Maybe you’ve read it in the papers?” John suggested. “The case of the smuggled Chinese artefacts, or the experiments down at Baskerville military base?”

“No, doesn’t ring a bell,” the Doctor mused, still obviously trying to remember.

“So, you’re not one of Mycroft’s people, then?” John enquired. “Some kind of secret agent or specialist he’s trying to keep under wraps. That’s why you call yourself ‘the Doctor’? Is it a codename?”

“Who is Mycroft?” the Doctor asked, increasingly confused by this man who seemed to know both more and less about what was going on.

“Well, some would say he is the British government nowadays,” John explained.

“We don’t have time for this,” the Doctor seemed to regain his composure, and turned around to pursue his search again. “One thing I can tell you, though, I am not anybody’s agent.”

John followed him, intent on asking until he got some answers, but he was suddenly struck silent as they’d apparently reached the end of the tunnel. 

The corridor opened into a high ceiling room, the old brick walls draped with moss and a scent of stale mould rising from the inches of water covering the ground. One corner of the bolted ceiling appeared to have recently caved in, as a pile of loose bricks cluttered near the wall. But that’s not what made John doubt he was seeing right. Transparent greenish cocoons covered in slime stuck to the walls on either side, some of them smaller, other ones the size of a fully grown man, and if he squinted just right, John could make out the shape of some living creature inside the one closest to him.

“Ah, there you are!” the Doctor exclaimed, unperturbed.

John was trying to get his wits about him and close the jaw he felt was hanging dumbly open, when the first blow landed to the back of his head.

 

*


	5. Chapter 5

Sherlock bumped into Amy and Rory just as he was about to turn around and go back the other way to find John. 

“You!” he said, looking at Amy, part of him pleased at having his deductions confirmed. 

“Who are you and why are you staring at me like that?” Amy bristled.

“Wait, I know you,” Rory said. “You’re that detective bloke from the newspaper, the one with the hat. Sherlock... something.”

“Yes, I am Sherlock Holmes and, no, I do not wear a hat,” Sherlock said in his annoyed monotone. “Why are you here? What are you looking for?”

“I don’t think that’s any of your business,” the girl replied testily.

“Amy, I’ve read this guy’s blog,” Rory intervened. “He’s supposed to be wicked smart at solving cases, maybe he can help us.”

“Oi, we can handle it by ourselves Rory, we don’t need him!” Amy protested and geared up to continue her tirade, but was interrupted by Rory’s gasp:

“Uh-oh, you might want to rethink that,” he said, looking with shocked wide eyes over Sherlock’s shoulder.

Sherlock spun around just in time to duck a blow aimed at his head by what looked like a creature straight out of a science fiction show. It was slightly shorter than average human height, had green scaly skin covering what he could see of its body, a long reptilian tail, its head and neck elongated like that of a snake, while its limbs appeared to have three joints instead of two, ending in four sharp claws. For a second, his mind skidded to a halt, refusing to acknowledge this thing that defied every logical explanation; he briefly flashed back to the incident at Baskerville and wondered whether he was again under the influence of some kind of drug, but quickly decided to dismiss that idea when the creature swung one of its clawed arms towards his face.

He ducked back once again and reached for his gun, but before he could raise it, the creature took a swipe with its long tail and knocked it out of his hand. He heard a frightened yelp from behind and caught sight of another creature approaching the couple he had just met. He was caught by surprise when the first creature lunged itself at him, knocking him to the ground. Sherlock pushed his arms forward to block the thing’s claws from reaching his throat. Its skin felt cold and slippery under his hands and it was obviously strong enough to overpower him. The thing’s lidless black eyes pinned him while it opened its mouth with a low hissing sound. A flexible tongue ending in what appeared to be a sharp, curved spike snaked out, ready to strike. 

Instinct took over and Sherlock kicked as hard as he could, managing to dislodge the creature’s hold and roll back to his feet. He reached inside his coat and grabbed the Kurdish dagger he kept with him at all times, swinging it towards the creature and managing to hit it in the arm. The thing retaliated with a well-aimed swipe of its claw that caught his left shoulder, cutting through fabric and skin. They danced around each other, exchanging and deflecting blows, until Sherlock managed to pull a particularly tricky manoeuver that granted him just enough space to plunge the dagger into the creature’s chest and twist it, so that the curved tip would inflict as much internal damage as it could. The creature wailed and dropped to the ground, but not before it thrust its tongue out one last time and pricked the skin on Sherlock’s wrist just below the cuff of his coat.

In the span of one second, his mind flooded with all the data he had ever acquired about snakebites, dispersion rate of venom and possible effects, then he locked his lips to the wound and began sucking out the infected blood from the bite. He spat out the liquid and repeated the process, all the while trying to keep his heart rate stable, so as not to accelerate the blood flow and further spread the poison into his system. 

Another yell made him look up and see Amy and Rory grappling with the other creature and losing ground fast. He scrambled to pick up his gun from where it had been thrown earlier, and raised it with a shout:

“Get down!”

Both Rory and Amy dropped to the ground, while Sherlock took aim and shot the creature right between the eyes. It fell with a thud in the sudden silence.

Helping Amy to her feet again, Rory uttered in newfound respect:

“Wow! Where did you learn to fight like that?”

“Iranian Revolutionary Guard,” Sherlock answered, wiping the blade and resheathing it, while he took in their state.

“Are you alright?” he asked.

“Yes, yes, we are,” Amy said clearing her throat. “I guess you’re kind of useful to have around after all.”

After a pause:

“I’m Amy, by the way, and this is my husband, Rory.”

“Nice to meet you,” Sherlock said in his usual tone that brooked no argument. “But would you mind telling me what those things were?”

“Shitakene!” Rory piped up.

“No, doofus,” Amy rolled her eyes. “Serashene.”

“Aliens!” Rory spoke over her.

“I beg your pardon?” Sherlock gave them a disbelieving look.

“Extinct race of aliens…” Amy began.

“Or so we thought until a week ago.” Rory supplied.

“…surviving for millennia underground as frozen spores, knocked into action by the drilling going on lately, who like to attach themselves to people and try to rewrite their DNA.”

“That is the most ridiculous thing I have ever heard,” Sherlock found himself, probably for the first time in his life, utterly confused.

“Well, how do you explain those two over there, then?” Amy challenged.

“Right…” Sherlock glanced at the splayed bodies of the hideous things that had attacked them. His mind was spinning and he could no longer find refuge in the cold, hard facts like usual; everything he thought he knew, all logic had been thrown out the window and he felt off kilter, bereft. He was beginning to doubt the only certainty he’d always had: his judgement. What was he supposed to do now?

He gradually registered the argument between Amy and Rory that had been going while he was lost in thought.

“…need to get out of here… don’t know how many there are…”

“…find him. He’s got to have a plan, he always has a plan…”

“I’m not going to risk losing you because of this, Amy! We’re in way over our heads…”

That’s when Sherlock suddenly remembered. The man, the one he had been looking for! He turned towards the other two and was about to ask, when –

“Hands in the air!” the shout shut them all up and froze them to the spot.

At once, a group of men wearing hazmat suits and holding guns encircled them.

“Oh, great!” Sherlock huffed, recognising Mycroft’s people.

“Nobody move,” another one of them said, as three of the suits approached them to search for weapons, while others crouched down to examine the two alien bodies.

They pulled out Sherlock’s gun and knife and pushed him to stand next to Amy and Rory.

“Who are you and what are you doing here?” the first one who had spoken approached.

“My name is Sherlock Holmes and, judging by your awful suits and obviously lacking technique, you must be the cleanup crew.”

One of the men paced a few steps back and started to speak into a walkie talkie: “We’ve got Sherlock Holmes and two civilians at the site… yes, sir…”

Sherlock let his eyes roam over the men with a calculating look.

“Are you going to kill us?” Rory spoke up.

“No, we are not,” the obvious leader of the team spoke. “But this area is under quarantine, you have no business being here. You will follow us out immediately.”

“Oh, I don’t think so,” Sherlock said calmly. “There are two more people down here in these tunnels and we are not leaving without them.”

“Well, sir, I don’t think you have a choice,” the man snarked and raised his gun to Sherlock’s chest.

With a well-practised move, Sherlock grabbed the man’s wrist, twisted it, snatched the gun and pointed it at his head, holding him in an armlock, while the rest of the suits turned with their weapons poised.

“Run!” Sherlock told Amy and Rory, without letting the men out of his sight.

“Wait, what about you?” Amy asked.

“Don’t worry about me, just go!”

The two of them spun round and dashed away into the tunnel.

“Stay where you are,” he warned. “Or I will shoot.”

The men looked torn, watching the scene.

“Really, mister Holmes?” the man he was holding hostage said. “How do you think this is going to end?”

With a quick glance to the ceiling, Sherlock replied:

“Exactly how I want it to.”

He pointed the gun up and shot clear through the water pipe than hung above their heads. Immediately, a thick spray of water flooded the scene, obstructing their view, and Sherlock used the moment of confusion to disentangle himself from his hostage and run in the direction the others had gone, as fast as his long legs could take him.

He’d covered a respectable distance before the men snapped out of it and started to follow. He had to time it just right…

He reached Amy and Rory who greeted him in surprise and kept running.

“Now, if my calculations are correct, there should be a shaft right about… here!” he said as he pulled the other two to a halt just below where a maintenance shaft was carved six feet above ground into the wall. The entrance was camouflaged by the dark and barely discernible if someone wasn’t looking for it particularly.

“Up, up, up!” he said, and helped give Rory and Amy a boost into the narrow passage, then flung himself upward and joined them inside the crammed space, just as their pursuers were coming into view.

With their flashlights turned off and holding their breaths, they waited until the group of men had passed, then quietly descended and ran the other way.

After they managed to reach a safe distance through the maze, Amy was finally able to ask:

“How did you know that niche would be there?”

“I memorised the map,” Sherlock answered.

“You mean the entire London underground map?” she couldn’t hide her disbelief.

“Yes,” he replied, giving no further explanation.

“Man, you are brilliant!” Rory exclaimed with a laugh. “And insane.”

“Nonsense,” Sherlock deflected. “I am the sanest person I know.”

“Oh, he’s gonna like you,” Amy murmured, shaking her head.

“Where are we going?” Rory asked before Sherlock could inquire about the comment.

“To find my colleague and your friend,” Sherlock answered. “And then we have to get out of here as soon as possible.”

“Because of the creatures?” Amy asked.

“Yes, that too, but we have a more pressing problem right now,” Sherlock explained as he led the way, turning left and right through the maze of corridors towards the general direction he believed John had gone judging by their position when they had split up.

“Look at your feet,” he prompted. “What do you see?”

“A whole lot of mud and I don’t even want to know what else,” Rory replied.

“And as you might remember, half an hour ago there were four steady inches of water flowing through all the tunnels, that is why your boots are currently soaked.”

“You’re right, it stopped,” Amy said. “What does that mean?”

“It means they’re sealing the tunnels up,” Sherlock replied. “They’re planning to deal with your little alien problem the old fashioned way, and from my experience with the cleanup crew, their method of choice is fire.”

“Oh my God, they’re gonna blow us up!” Rory gasped.

“Not if I can help it,” Sherlock sneered. “Now, come on!”

 

*


	6. Chapter 6

The fight – if being knocked out by a hit to the head and then tied up to become someone else’s meal could be called fighting – had left the Doctor a bit loopy. 

“We come in peace,” he tried again for the more diplomatic approach.

He could tell it didn’t work when he got slapped across the face by a slimy tail for his trouble. The other man, John Watson, was still out for the count, slumped against the wall in oblivious slumber. He twisted his arms against the ropes to no avail, watching the three Serashene communicate in their strange hissing language. From what the Tardis’ automatic translation allowed, they were apparently trying to decide whether to eat them or use them as incubators for their offspring. This was not the way the Doctor had envisioned fatherhood.

He spared a moment to think what his offspring might look like if he were indeed to suffer such a fate, and giggled amusedly, which earned him another slap across his cheek. That definitely didn’t help with the dizziness and growing headache.

Despite all his good intentions, there was no reasoning with the Serashene. They were intent on spreading their genes to the entirety of Earth’s population, turning them into walking incubators like they had done to the three missing people that week. He could see the stasis capsule sitting innocuously in one corner of the room, near the end of a row of four day old ‘children’ that hadn’t hatched yet. 

He hated having to do this, having to choose between two races, to decide which one would live and which one would die. He’d had more than his fair share of hard choices to make in this life and he was tired of playing God. Still, he couldn’t stand by and watch the humans be destroyed. If he had one last haven of hope left, one place to almost call home among the vastness of space and time, it was Earth, and he was rather – oh, who was he kidding? very – attached to it. When it came down to it, there really wasn’t a choice between human and Serashene. Besides, they had taken his sonic screwdriver, damn it!

To his right, the other man started to stir awake.

A rustling sound echoed across the tunnel walls, coming from the darkness that stretched outside the room. The Serashene turned their heads in synch towards the entrance. As the other two nodded in unspoken agreement, one of them walked out into the tunnel to find the source of the sound. Not a minute later, a louder thud broke the silence, hinting that something was definitely not right. With a glance towards their prisoners to make sure they were still restrained, the last two Serashene darted out of the room and quickly after, the sound of grappling reached their ears. The Doctor looked at John and a large grin spread across his face:

“The cavalry is here!”

As John took in the room, blinking the fog from his brain, he groaned:

“Oh, God, it wasn’t a dream.”

“The interesting ones never are!” the Doctor replied cheerfully, as Amy dashed into the room and almost landed in his lap, hugging the daylights out of him.

“Doctor! I’m so glad you’re alive!”

“Yes, yes, I’m glad to see you too, Amy,” he struggled to breathe. “But could you untie me first, please?”

“I’ve got a knife,” John said, as Amy disentangled herself from the Doctor. “My pants, left pocket.”

Amy took the knife out and started to make quick work of the ropes.

“We’ve got to get out of here,” she said. “This whole place is going to blow up!”

Just then, Rory flew backwards through the air and landed in the middle of the room with a yelp. One of the Serashene came trudging forward, poised to attack, when Sherlock jumped it from behind and caught its neck in a tight grip.

“Can we hurry this up?” he ground through his teeth, struggling to hold the creature.

As soon as the Doctor was free of his restraints, he stumbled to his feet and scanned the room for something to hit the creature with. He snatched a brick from the pile on the ground just as the Serashene managed to shake Sherlock’s hold and spun around to attack. He darted forward and smashed the brick into the creature’s head, knocking it unconscious.

As the Serashene slumped to the ground, the Doctor bent to retrieve his sonic screwdriver, flipping it over in his hand, and muttered:

“Quid pro quo.”

Then he looked up at the man standing in front of him and… Oh!... Now, it all made sense.

He remembered floating in a state of pure consciousness, detached from his material form as his two hearts had ceased to beat. He’d welcomed the freedom for a second, for an eternity. And then, the pull, like his essence was being squeezed through the vacuum of space and time and crammed once more inside the too small receptacle of his flesh. It felt like dying, it felt like being reborn. The first thing that registered was blue, pale, endless blue like the deserts of Shankarra, a planet made of ice. But this ice was alive, this ice had depths in which he could get lost, sharp, calculating edges that threatened to dissect him to his very core and shed his many skins. For a moment, he felt afraid. 

That’s when he realised he was staring into somebody else’s eyes. A tall, lanky kid who wore the most endearing look of confusion on his face. It made him smile despite himself and for a few beats, he forgot to feel regret at being dragged back into life. He let himself stare and felt the hand splayed on his chest, between his two hearts, tether him to the here and now. Until he’d had to run again. His curse – his destiny? – to keep on running and never look back.

The ice was still as sharp as he remembered and the confusion was still the same. Only the kid had grown into a man.

“It’s you,” the man’s voice was low and muted with awe. “But still, you’re different… How can it be you?”

And the Doctor knew he was not only referring to his new face. The man could read him, could see the change and understand that the price of life meant losing bits and pieces of himself along the way. Oh yes, the man was sharp. The Doctor grinned and found his voice:

“Sherlock Holmes. I told you we’d meet again.”

 

*


	7. Chapter 7

“Wait, you two know each other?” Amy asked, squinting at the two of them. 

“Why am I not surprised?” John mumbled with a roll of his eyes.

“Should we, umm, give them a minute?” Rory asked, watching them with barely contained curiosity.

“What?” Amy pulled her eyes away from the scene to glare at her husband. “No! We have to get out of here, remember?”

She took a few steps forward and said in the most commanding tone she could muster:

“Doctor, snap out of it!”

The Time Lord blinked a couple of times as if waking up from a trance and cleared his throat.

“Right, leaving, gotcha!” he spun around. “Everybody accounted for? Ok? Let’s go!”

He took two steps towards the tunnel, then made an “Ah, wait!” as if he’d just remembered something. He spun around, went back into the room and grabbed the stasis capsule. It was a spherical container, made of what looked like metal, with no apparent lid or discontinuity on its surface. The Doctor quickly ran his sonic screwdriver over it and muttered: “Good, it’s sealed itself up again. Smart little thing, aren’t you?”.

He came back, ran his eyes over the group of four watching him curiously and said:

“Right, now we can go!”

He made to pull out his map, but Sherlock cut in:

“Follow me, I’ll get us to the nearest exit.”

He’d apparently shaken off his earlier stupor and now he wore the same expressionless, determined mien as before. He took off down the corridor, out through the metal door, then turned left and kept on going, the others following behind. 

For a second, as he made his way through the maze, Sherlock felt a sharp stab of pain shoot up his right arm, numbing is so that he almost dropped the flashlight he was holding. He muffled a grunt of pain, switched the torch to his other hand and kept going. These people’s lives were in his hands; he didn’t have time for questions or doubts and he wasn’t going to think about the bite on his wrist or what deadly alien poison was probably flowing through his veins. The pain receded after a few beats.

“Why did you bring that thing along?” Rory asked, pointing towards the sphere. “Aren’t you going to get infected touching it?”

“Oh, not to worry,” the Doctor said. “It’s closed for now. Whatever happened a week ago must have triggered an automatic dispersal sequence so that it only opens once every 48 hours to release a small amount of spores. If the last disappearance took place at three o’clock last night, and the medium incubation period, before the hosts’ bodies give out, is six to seven hours, the last time it opened was around eight o’clock in the evening, the day before yesterday.”

“Coincides with the victims’ timetables,” Sherlock said. “Penny Clayworth usually finished work at seven, but on Monday she had a last minute appointment with a new client and was delayed. Clark Turner’s last Wednesday lecture takes place every week from 6 to 8. Russel Cox went to do his monthly bookkeeping on Friday and one of his waitresses saw him leave at quarter to eight. They all must have taken the 8:15 tube.”

“But, Doctor, you said the spores attach themselves to any living person they find,” Amy said. “Why were only these three people infected?”

“That we know of,” the Doctor said. “These are the only three disappearances that tipped off the police. From what I can tell, a human host can only carry up to five Serashene embryos. But there are well over forty offspring in different stages of growth in the room we just saw, not including the ones that have already hatched.”

“That’s why we couldn’t see any homeless people in this tunnel, when usually this is where they hide out during the night,” Sherlock mused.

“This is insane! Aliens, mutant viruses… ” John exclaimed, turning towards Sherlock. “Why aren’t you more freaked about all this?”

“Well, John,” Sherlock answered sarcastically. “Panicking isn’t going to help us escape before we get blown to bits, now, is it?”

“Yeah, about that,” John resumed. “How do you know?”

“We had a run in with some of Mycroft’s men, and they’ve begun sealing off the tunnels,” Sherlock said. “We don’t have much time.”

“Blowing the place up isn’t going to do anything to stop it,” said the Doctor. “It may destroy the already born Serashene, but this capsule has travelled to Earth from the opposite end of the universe and lasted here for sixty million years. A little explosion isn’t even going to ping it.”

“So it’s going to open again tonight at 8, no matter what!” Rory said.

“If I can get it back to the Tardis, I may be able to reprogram the opening sequence…” the Doctor began.

“Damn!” Sherlock exclaimed, skidding to a halt.

The tunnel in front of them was blocked by what looked to be a thick slab of metal, cutting off their exit.

“Oh, God, what are we going to do?” asked Rory, feeling the panic take over.

“Find another way,” growled Sherlock, turning back the other way. “Come on!”

They retraced their way to a junction of tunnels and were ready to pursue an alternate route, when the clicking sound of several guns trained at their backs made them stop and turn around to see the same group of men wearing protection suits they had met earlier.

Their leader took a step forward and smirked through the transparent screen of his helmet.

“Mister Holmes, I see you’ve found your friends.”

John made an imperceptible move to his coat pocket, where he kept his own gun, but Sherlock caught his eye and shook his head minutely.

“I do hope you’ll come quietly this time, or we might just have to leave you here,” the man continued, and motioned for a few of his men to restrain them.

They did a quick search for weapons and took the metal sphere from the Doctor, sealing in inside an airtight container one of the men held. The man who approached Sherlock to search his pockets hesitated for a second, eliciting a smirk from Sherlock:

“Go on then, I’m not going to bite.”

The leader smacked him across the cheek with the butt of his handgun.

“If I didn’t have specific orders to keep you alive, don’t think I wouldn’t enjoy making collateral damage out of you, Mister Holmes, for the stunt you pulled earlier,” he threatened. “They did say ‘alive’, however, not unharmed, so keep that in mind next time you make another smart remark. Now, move!”

Still keeping their guns poised, the men ushered them forward.

 

*

 

Fifteen minutes later, they were all standing above ground once more, in a warehouse area near the banks of the river Thames. The sun was starting to peak above the horizon, throwing a weak tinge of crimson over the bleak surroundings.

“Perimeter contained and subjects extracted,” the leader of the team spoke in his radio transmitter. “You can give the order now, Sir.”

“Copy that, Sergeant Simmons.” a voice crackled through the speaker. “Five minutes to mark.”

Two vans and a black sedan were approaching from the main road.

“Tell me, Sergeant Simmons,” Sherlock narrowed his eyes at the man. “Do the military only recruit blubbering idiots, or did they make an exception for you?”

The man took a step towards him with a snarl and smashed the rear end of his rifle into his stomach, as hard as he could. Sherlock doubled over with a grunt and staggered sideways, the Doctor catching his arm and steadying him before he could fall.

”I told you to keep your mouth shut!” the Sergeant snapped.

Before he could lift the gun to strike again, the sound of someone clearing their throat came from where the black car had pulled over a few feet behind.

The Sergeant quickly straightened his stance and greeted with a clipped, military: “Sir!”

Mycroft was leaning casually with a hand on his ever present umbrella, watching the scene disinterestedly. His eyes roamed over the group and widened minutely upon landing on the Doctor’s face.

“The Doctor,” he said. “I’ve been waiting to meet you for a long time.”

He turned towards Sergeant Simmons and ordered:

“Take him and his two companions to the van.”

Three men grabbed Amy, Rory and the Doctor and pushed them towards one of the vans, while the other members of the containment team piled into the other.

“Where are you taking us?” Amy asked, struggling against the men’s hold.

“Don’t worry, we’re only going to have a little chat,” Mycroft answered as the doors to the van were closed behind the three.

Sherlock gritted his teeth as the van pulled out. Mycroft turned towards him and John.

“I see you chose not to heed my advice as usual, little brother,” he said in a patronising tone. “Come on, let’s get you home.”

“I’m not going anywhere until you tell me what’s going on.” Sherlock crossed his arms stubbornly.

“Get in the car, Sherlock, and stop acting like a five year old who just lost his toy,” Mycroft said testily. “This isn’t the place to have this discussion.”

“Fine,” Sherlock bit out through clenched teeth and entered the car, followed by John and his brother.

Once they had settled and the car started towards Baker Street, Sherlock fixed his brother with a level stare and demanded:

“Well?”

Mycroft sighed, like the weight of the whole world strained on his shoulders, and said:

“Since you’ve seen it for yourself already, I guess there is no point in beating around the bush anymore.”

Sherlock waited in silence, unwilling to relent, and after a pause, Mycroft resumed:

“Have you ever heard of the name ‘Torchwood’?”

Under them, the ground rumbled and shook with the aftershocks of the explosion as the car drove on.

 

*


	8. Chapter 8

“There is no way to talk you out of this, is there?” John asked resignedly.

Sherlock’s pointed look said it all. He continued to pile weapons and electrical equipment into the black duffel bag.

“Then I’m coming with you,” John said, holstering his gun.

Sherlock was uncharacteristically quiet and moved with the kind of calm precision that foreshadowed a storm. John’s mind was spinning with the new information and he kept waiting to wake up from this crazy dream. Nothing would ever be the same again.

“How are we going to find him?” he asked.

“Tracker,” Sherlock supplied. “I planted one on him earlier.”

John flashed back to the moment the Sergeant had hit his friend. Smooth.

“Alright, then,” John sighed. “I believe you have a plan?”

**

At 7:25 PM the entire Western London power grid shut down. Traffic lights went out, security systems failed and people started panicking as night began to fall. John took a moment to smash the security guard’s chair into the main computer’s screen, then stepped over the three unconscious men with a satisfied grin. It would take them a while to fix this.

*

At 7:26, the auxiliary generator kicked in and lights flickered briefly in the windows of the twenty storey high government building, before they turned back off again. Technicians typed furiously on their now useless keyboards, trying in vain to find the source of the virus that had caused all systems to crash. 

Inside his office, Mycroft Holmes rose from his chair and ordered:

“Get me security!”

“Sir,” Anthea said checking her mobile phone only to find no signal. “Communications are down.” Picking up the phone receiver off her desk: “Landlines as well.”

Mycroft took three steps towards the door and tried to open it, only to find the building’s emergency lockdown sequence had closed all exits, including this one. Gritting his teeth until he could almost feel them crack, he growled under his breath:

“Sherlock!”

*

At 7:32, the door to the containment cell clanked open to reveal the hunched figure of a man inside, strapped to a chair, with his head bent to his chest. Blood was dripping from his nose, staining the wavy-patterned shirt underneath.

“They really did a number on you,” Sherlock observed from the doorway.

The Doctor raised his head and a wide grin spread across his face as the other man approached.

“They wanted answers, I didn’t oblige,” he said.

“We’ve got fifteen minutes until systems reboot,” Sherlock said, quickly untying the straps around the Doctor’s arms and legs. “Can you walk?”

“Don’t worry, us Time Lords heal fast,” the Doctor said as he rose unsteadily to his feet.

“You have some explaining to do, Doctor,” Sherlock said as they made their way out of the room, sidestepping the four unconscious men lying on the floor and continuing down the hall. “But first, we need to find your friends.”

The Doctor pulled out his sonic from the inner pocket of his jacket and swirled it towards one of the offline security screens embedded in the wall, as they passed.

“Oh, that is beautiful!” he exclaimed as he checked the readings of the virus infecting the mainframe. “By 21st century human standards, this is actually impressive. Where did you get it?”

“You have your sources, I have mine,” Sherlock replied cryptically.

“There’s more to you than meets the eye, Sherlock Holmes,” the Doctor shook his head, impressed despite himself with the man.

They reached another deadlocked door which the Doctor made quick work of with his sonic and entered the cell where Amy and Rory were being held.

“Doctor!” the girl exclaimed in surprise. “I knew you’d find a way out!”

“Don’t look at me, I’m only along for the ride,” the Doctor grinned, nodding towards Sherlock.

“Mister Holmes,” Rory began. “I don’t know how to thank you…”

“Yes, sure, but can we do this later?” Sherlock interrupted impatiently. “We are on a schedule here.”

“Right!” Amy said. “Where to, then?”

“Follow me,” he said as he led them through the halls towards the only exit he had left open.

They bumped into a group of security guards along the way, but easily took them out and kept running. Sherlock felt a sudden burst of pain shoot through his body that made him almost stagger and lose his footing. They were getting increasingly frequent now and harder to ignore.

“Are you alright, mate?” Rory eyed him from his left.

“Yes, yes, I’m fine,” he snapped as the pain subsided. “Keep going!”

“Wait!” the Doctor stopped abruptly. “The capsule! We need to get it before…”

“Already taken care of,” said Sherlock and ushered him forward, as they neared the exit. Without breaking his stride, he bent to pick up the sealed case he’d left near the door that held the capsule he had previously retrieved from the lab.

They burst out the doors just as a large dark-green car screeched to a halt in front of the building.

“Get in!” John shouted as he threw open the passenger side door.

They quickly piled inside, and peeled down the street just as the lights started flickering to life again in the building, and government agents came running out the now unlocked doors.

“Where are we going?” John asked from behind the wheel.

“We need to get to my Tardis,”the Doctor said. “I parked it near the West end of Hyde Park. Do you think you can get us there in fifteen minutes?”

“Oh, I’ll get us there,” John said as he bypassed the main street and swerved into a narrow alley. “I know a shortcut.”

“What in God’s name happened to all the lights?” Rory asked, eyeing the darkened city through the window.

“Sherlock’s idea,” John explained, as he made his way through the increasingly shady looking side streets. “To delay Mycroft’s pursuit.”

“My brother’s always enjoyed a good game of hide and seek,” Sherlock smirked.

“You mean that man is your brother?” the Doctor was taken aback.

“Wait, it was your idea to take out half of London’s power supply?” Amy stared at him in disbelief. “Are you out of your mind?”

“You’re like the bloody 007 or something!” Rory gaped at him in awe.

“Oh, please, stop feeding his ego,” John rolled his eyes from the front seat. “It’s big enough already.”

Twelve minutes later, they were stopping next to the blue police box carefully parked on a corner that wasn’t in direct view of any nearby CCTV cameras. They got out of the car and waited as the Doctor fished out his key and unlocked the door.

“Welcome to my humble abode!” the Doctor grinned at them for a second, before he scurried up the stairs to the main console, pulled the sphere out of its case and began attaching wires to it.

Sherlock and John paused in their tracks, taking it all in with matching expressions of awe.

“What the…?” John muttered.

“I know, it’s bigger on the inside!” the Doctor said proudly as he started typing something on one of the keyboards. “Now, if I could just rewire the… Damn! It’s encrypted!”

“It’s a spaceship!” John whispered, oblivious to all. “I’m inside an honest-to-God spaceship!”

“Doctor, hurry up!” Amy said, looking at her watch. Thirty seconds to 8.

“I’m trying!” he huffed, attacking the keys with new vigour. “Come on… Reroute tricyllic stabilisers, bypass embedded matrix by two- no, three! - degrees, rehash secondary failsafe to one…”

“Doctor…!” Amy prompted with concern. One second left.

“Aaand… enter!” the Doctor punched the last key.

They both held their breaths, but nothing happened, the sphere remained closed.

“Yes!” the Doctor bounced on his feet. “It worked!”

Sherlock was snapped out of his daze by another jolt of pain that went through his entire body, the most painful one so far, and his feet were swept from under him at the unbearable feeling of being burned from the inside out.

The hard thud made all the others spin towards him.

“Sherlock!” John fell to his knees beside his friend, taking in his twisted features and obvious pain.

“What’s wrong with him?” Rory asked. 

“I don’t know,” John mumbled in panic as he took Sherlock’s vitals.

The Doctor kneeled on his other side and turned the man’s head towards him, staring at his pupils. There were thin, black lines stretching like a web across his corneas. Sherlock writhed under a new jolt of white-hot-searing pain and let out a scream through his clenched teeth.

“How long has he been like this?” the Doctor asked, dread creeping up on him as he guessed what the problem might be.

“I don’t know!” John exclaimed, feeling helpless and scared. “I didn’t notice anything different! We were kind of distracted by all of the… Oh, Jesus, how could I not see that -” 

“I saw him almost trip on his own feet earlier,” Rory piped up. “He looked like he was in pain, but he said it was nothing…”

The Doctor spurred into action and began to check the man over. He caught a glimpse of something under his shirt cuff and prompted:

“Help me get this off!”

John and him scrambled to peel off Sherlock’s suit jacket and shirt.

“Oh my God!” Amy gasped from behind.

On Sherlock’s wrist there stood a dark, swollen lump with a puncture mark in the middle, and from it, black veins stretched in relief across his arm, up to his shoulder and a ways down his right pectoral. They seemed to spread further as they watched the man writhe, every fibre of his body taut.

“Sherlock! Can you hear me?” the Doctor squeezed the man’s face between his hands.

He thrashed again as wave after wave of unimaginable hurt flooded him. He couldn’t hold back a half-groan, half-whimper of pain.

“Sherlock, this is important. How long ago were you bitten?” He waited a beat. “How long?” he asked more forcefully.

Sherlock struggled to breathe through the pain and think.

“Down… in the… tunnels,” he ground out through his teeth. “Twelve… thirteen hours…”

Then another scream was ripped from his throat. All of them flinched at the sound.

“Damn it!” the Doctor clenched a hand into his own hair, his thoughts whirring. “Help me get him to the medical bay, now!”

Between him, Rory and John, they carried him off the floor, along one of the Tardis’ corridors, to a white, brightly lit room. They lay him on the large operating platform in the middle, surrounded by various hulking machines and the Doctor hurried across the room to a wall that was covered in rows of thin, translucent disks, all stacked neatly against each other with labels in Gallifreyan marking the categories. He rifled quickly through them until he found the one he was looking for, then ran back to the platform and powered up one of the machines.

“Oh God, oh Jesus…” John was fretting. “Is he going to be alright?”

“Serashene venom,” the Doctor said, as he inserted the disc into the machine and began typing the specifics into the main drive. “Spreads itself through the victim’s body and permeates the tissue, binding itself to the cells. When it reaches critical level, it starts to dissolve them, until the main functions of the body give out. It is not quick or merciful, it was specifically designed by the Serashene to inflict the maximum amount of pain. This is unnecessary and cruel!” he spat out furiously as he hurried to the other side of the operating table to adjust some controls.

Sherlock’s body was slowly going into shock. He seemed to have lost awareness, but his muscles still shook with unrestrained tremors. The black web of veins had spread completely over his chest.

“How long?” John choked out. “How long until it reaches critical?”

“Twelve hours.” The Doctor muttered darkly.

“Oh, God,” John felt like the world was spinning around him. “It’s too late!”

“He’s fighting it, the symptoms were delayed,” the Doctor said. “He must have received a smaller dose, or he treated it somehow – “

“Can you save him, Doctor?” John could hear himself pleading, but he didn’t care.

“I will save him.” The Doctor said in a tone that carried centuries of wars fought and won, sheer stubbornness and determination to bend the workings of time and space to his will. 

He realised that he had been squeezing the unconscious man’s hand in his. He forced himself to let go and pushed the final button that put the machine into motion.

A luminous energy field encased Sherlock’s body and the tremors ceased.

“What now?” asked Amy in a quiet, forlorn voice.

“Now, we wait.”

 

*


End file.
